2019-09-02 12:11:31 +08:00
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# Nasal Interpreter
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2019-08-28 23:03:31 +08:00
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2019-07-25 02:14:33 +08:00
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# Nasal
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Nasal is a script language that used in FlightGear.
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There is a Nasal console in FlightGear but sometimes it is not so easy for every developer to use.
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So this is an interpreter for Nasal written by C++.
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2019-07-25 02:17:35 +08:00
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The interpreter is still in development.Anyone who interested in this could also join us!
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2019-07-28 00:06:29 +08:00
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2019-08-25 00:41:12 +08:00
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2019-09-09 22:55:05 +08:00
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# Now complete add and sub in abstract syntax tree
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2019-07-28 00:06:29 +08:00
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2019-09-09 22:55:05 +08:00
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And add a command 'ast' to see the AST
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2019-07-28 00:06:29 +08:00
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2019-09-09 22:55:05 +08:00
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and command 'run' can give you the result
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2019-07-28 00:06:29 +08:00
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2019-07-29 21:50:18 +08:00
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# Now complete Lexical Analysis!
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2019-07-28 00:06:29 +08:00
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2019-09-25 20:49:06 +08:00
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What do it's outputs look like?
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Identifier | engineTimer )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Operator | . )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Identifier | start )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Operator | ( )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Operator | ) )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Operator | ; )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( ReserveWord | print )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Operator | ( )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( String | "Engine started" )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Operator | ) )
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2019-07-29 21:50:18 +08:00
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2019-07-30 21:01:04 +08:00
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( Operator | ; )
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2019-07-29 21:50:18 +08:00
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This is what it outputs.
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2019-08-07 02:48:03 +08:00
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2019-08-28 15:37:21 +08:00
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# Push down automata
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After many times of failure,i finally try to use PDA to do the parse work.
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2019-09-25 20:49:06 +08:00
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But something occurred,so i finally didn't make it.However you can still see this LL(1) and LR(0) parser in version 0.7 & 0.9
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# Now complete Parser
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The parser can recognize some basic elements in resource program.
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And in future i will make it to support more flexible grammar.
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2019-10-01 23:16:04 +08:00
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# Calculator
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You can try a calculator in version 0.17~0.19 !
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